Reduced mechanical efficiency in left-ventricular trabeculae of the spontaneously hypertensive rat.

Long-term systemic arterial hypertension, and its associated compensatory response of left-ventricular hypertrophy, is fatal. This disease leads to cardiac failure and culminates in death. The spontaneously hypertensive rat (SHR) is an excellent animal model for studying this pathology, suffering from ventricular failure beginning at about 18 months of age. In this study, we isolated left-ventricular trabeculae from SHR-F hearts and contrasted their mechanoenergetic performance with those from nonfailing SHR (SHR-NF) and normotensive Wistar rats. Our results show that, whereas the performance of the SHR-F differed little from that of the SHR-NF, both SHR groups performed less stress-length work than that of Wistar trabeculae. Their lower work output arose from reduced ability to produce sufficient force and shortening. Neither their heat production nor their enthalpy output (the sum of work and heat), particularly the energy cost of Ca(2+) cycling, differed from that of the Wistar controls. Consequently, mechanical efficiency (the ratio of work to change of enthalpy) of both SHR groups was lower than that of the Wistar trabeculae. Our data suggest that in hypertension-induced left-ventricular hypertrophy, the mechanical performance of the tissue is compromised such that myocardial efficiency is reduced

Thin-film composite membrane on a compacted woven backing fabric for pressure assisted osmosis

© 2016 Elsevier B.V. The water flux in forward osmosis (FO) process declines substantially when the draw solution (DS) concentration reaches closer to the point of osmotic equilibrium with the feed solution (FS). Using external hydraulic pressure alongside the osmotic driving force in the pressure assisted osmosis (PAO) has been found effective in terms of enhancing water flux and even potentially diluting the DS beyond osmotic equilibrium. The net gain in water flux due to the applied pressure in the PAO process closely depends on the permeability of the FO membrane. The commercial flat sheet cellulose triacetate (CTA) FO membrane has low water permeability and hence the effective gain in water flux in the PAO process is low. In this study, a high performance thin film composite membrane was developed especially for the PAO process through casting polyethersulfone (PES) polymer solution on a compacted woven fabric mesh support followed by interfacial polymerisation for polyamide active layer. This PAO membrane possesses a water flux of 37 L m2h− 1using 0.5 M NaCl as DS and deionised water as the feed at an applied hydraulic pressure of 10 bar. Besides, the membrane was able to endure the external hydraulic pressure required for the PAO process owing to the embedded backing fabric support. While the membranes with low structural parameters are essential for higher water flux, this study shows that for PAO process, polymeric membranes with larger structural parameters may not be suitable for PAO. They generally resulted in compaction and poor mechanical strength to withstand hydraulic pressure

Sulfur-containing air pollutants as draw solution for fertilizer drawn forward osmosis desalination process for irrigation use

© 2017 Elsevier B.V. This study investigated suitability and performance of the sulfur-based seed solution (SBSS) as a draw solution (DS), a byproduct taken from the photoelectrochemical (PEC) process where the SBSS is used as an electrolyte for H2 production. This SBSS DS is composed of a mixture of ammonium sulfate ((NH4)2SO4) and ammonium sulfite ((NH4)2SO3), and it can be utilized as fertilizer for fertilizer drawn forward osmosis (FDFO) desalination of saline water. The FDFO process employed with thin-film composite (TFC) membrane and showed that the process performance (i.e. water flux and reverse salt flux) is better than that with cellulose triacetate (CTA) membrane. In addition, it produced high water flux of 19 LMH using SBSS as DS at equivalent concentration at 1 M and 5 g/L NaCl of feed solution (model saline water). Experimental results showed that the reverse salt flux of SBSS increased with the increase in pH of the DS and that lowering the concentration of ammonium sulfite in the SBSS led to the higher water flux of feed solution. The result also demonstrated that this SBSS is practically suitable for the FDFO process toward development of water-energy-food nexus technology using sulfur chemicals-containing air pollutant

Modification of nanofiber support layer for thin film composite forward osmosis membranes via layer-by-layer polyelectrolyte deposition

© 2018 by the authors. Licensee MDPI, Basel, Switzerland. Electrospun nanofiber-supported thin film composite membranes are among the most promising membranes for seawater desalination via forward osmosis. In this study, a high-performance electrospun polyvinylidenefluoride (PVDF) nanofiber-supported thin film composite (TFC) membrane was successfully fabricated after molecular layer-by-layer polyelectrolyte deposition. Negatively-charged electrospun polyacrylic acid (PAA) nanofibers were deposited on electrospun PVDF nanofibers to form a support layer consisted of PVDF and PAA nanofibers. This resulted to a more hydrophilic support compared to the plain PVDF nanofiber support. The PVDF-PAA nanofiber support then underwent a layer-by-layer deposition of polyethylenimine (PEI) and PAA to form a polyelectrolyte layer on the nanofiber surface prior to interfacial polymerization, which forms the selective polyamide layer of TFC membranes. The resultant PVDF-LbL TFC membrane exhibited enhanced hydrophilicity and porosity, without sacrificing mechanical strength. As a result, it showed high pure water permeability and low structural parameter values of 4.12 L m−2 h−1 bar−1 and 221 µm, respectively, significantly better compared to commercial FO membrane. Layer-by-layer deposition of polyelectrolyte is therefore a useful and practical modification method for fabrication of high performance nanofiber-supported TFC membrane

Thin film composite hollow fibre forward osmosis membrane module for the desalination of brackish groundwater for fertigation

© 2015 Elsevier B.V. The performance of recently developed polyamide thin film composite hollow fibre forward osmosis (HFFO) membrane module was assessed for the desalination of brackish groundwater for fertigation. Four different fertilisers were used as draw solution (DS) with real BGW from the Murray-Darling Basin in Australia. Membrane charge and its electrostatic interactions with ions played a significant role in the performance of the HFFO module using fertiliser as DS. Negatively charged polyamide layer promotes sorption of multivalent cations such as Ca2+ enhancing ion flux and membrane scaling. Inorganic scaling occurred both on active layer and inside the support layer depending on the types of fertiliser DS used resulting in severe flux decline and this study therefore underscores the importance of selecting suitable fertilisers for the fertiliser drawn forward osmosis (FDFO) process. Water flux under active layer DS membrane orientation was about twice as high as the other orientation indicating the need to further optimise the membrane support structure formation. Water flux slightly improved at higher crossflow rates due to enhanced mass transfer on the fibre lumen side. At 45% packing density, HFFO could have three times more membrane area and four times more volumetric flux output for an equivalent 8040 cellulose triacetate flat-sheet FO membrane module

Distances from the Correlation between Galaxy Luminosities and Rotation Rates

A large luminosity--linewidth template sample is now available, improved absorption corrections have been derived, and there are a statistically significant number of galaxies with well determined distances to supply the zero point. A revised estimate of the Hubble Constant is H_0=77 +-4 km/s/Mpc where the error is the 95% probability statistical error. Systematic uncertainties are potentially twice as large.Comment: 21 pages, 9 figures. Invited chapter for the book `Post-Hipparcos Cosmic Candles', Eds. F. Caputo and A. Heck (Kluwer Academic Publishers, Dordrecht

Agrobacterium-mediated genetic transformation of Miscanthus sinensis

Miscanthus species are tall perennial rhizomatous grasses with C4 photosynthesis originating from East Asia, and they are considered as important bioenergy crops for biomass production. In this study, Agrobacterium-mediated transformation system for M. sinensis was developed using embryogenic calli derived from mature seeds. In order to establish a stable system, optimum conditions to obtain highly regenerable and transformation-competent embryogenic calli were investigated, and embryogenic calli were efficiently induced with callus induction medium containing 3 mg L-1 2,4-dichlorophenoxyacetic acid and 25 mM l-proline, at pH 5.7 with an induction temperature of 28 A degrees C. In addition, the embryogenic callus induction and regeneration potentials were compared between seven M. sinensis germplasms collected from several sites in Korea, which revealed that the germplasm SNU-M-045 had superior embryogenic callus induction and regeneration potentials. With this germplasm, the genetic transformation of M. sinensis was performed using Agrobacterium tumefaciens EHA105 carrying pCAMBIA1300 with a green fluorescence protein gene as a reporter. After putative transgenic plants were obtained, the genomic integration of transgenes was confirmed by genomic PCR, transgene expression was validated by Northern blot analysis, and the number of transgene integration was confirmed by DNA gel blot analysis. Furthermore, the Agrobacterium-mediated transformation of M. sinensis was also performed with pCAMBIA3301 which contains an herbicide resistance gene (BAR), and we obtained transgenic M. sinensis plants whose herbicide resistance was confirmed by spraying with BASTA(A (R)). Therefore, we have established a stable Agrobacterium-mediated transformation system for M. sinensis, and also successfully produced herbicide-resistant Miscanthus plants by introducing BAR gene via the established method.X111210Ysciescopu

Segregation discovery in a social network of companies

We introduce a framework for a data-driven analysis of segregation of minority groups in social networks, and challenge it on a complex scenario. The framework builds on quantitative measures of segregation, called segregation indexes, proposed in the social science literature. The segregation discovery problem consists of searching sub-graphs and sub-groups for which a reference segregation index is above a minimum threshold. A search algorithm is devised that solves the segregation problem. The framework is challenged on the analysis of segregation of social groups in the boards of directors of the real and large network of Italian companies connected through shared directors

Comment on Higgs Inflation and Naturalness

We rebut the recent claim (arXiv:0912.5463) that Einstein-frame scattering in the Higgs inflation model is unitary above the cut-off energy Lambda ~ Mp/xi. We show explicitly how unitarity problems arise in both the Einstein and Jordan frames of the theory. In a covariant gauge they arise from non-minimal Higgs self-couplings, which cannot be removed by field redefinitions because the target space is not flat. In unitary gauge, where there is only a single scalar which can be redefined to achieve canonical kinetic terms, the unitarity problems arise through non-minimal Higgs-gauge couplings.Comment: 5 pages, 1 figure V3: Journal Versio